This invention relates to augers and particularly to augers used for backfilling trenches and the like.
Such augers become worn after extensive use by virtue of their frictional engagement with soil, gravel, rocks, etc. during the backfilling operation. In order to protect the auger flightings from such wearing, adjustable wear plates are fastened adjacent the outer peripheral edge of the flighting. An example of such wear plates is shown in prior U.S. Pat. No. 3,362,092.
These prior wear plates include slots in their inner edges for receiving a bolt which extends through a hole adjacent the outer peripheral edge of the flighting. The bolt is tightened in the slot to hold the wear plate against movement. When the wear plate becomes worn, the bolts are loosened and the wear plate is moved radially outwardly, with the bolts riding in the slots.
One disadvantage which has been encountered with the type of wear plate shown in U.S. Pat. No. 3,362,092, is the difficulty in holding the wear plates against movement during operation of the auger. The bolts hold the plates against some frictional movement, but the forces encountered by the wear plates are so great that the wear plates are likely to move even though they are being held by the bolts. The bolts slide in the slots in response to encountering these great forces.
In prior devices, in order to prevent this movement, it was necessary to provide additional means for engaging the inner edges of the wear plates to hold them against movement in an inward radial direction. Usually this blocking means has been provided by bolting a plate to the flighting adjacent the inner peripheral edge of the wear plate. This blocking plate engages the inner peripheral edge of the wear plate and provides further reinforcement to prevent the inward radial movement of the wear plate.
The disadvantage of providing these inner blocking means is that the adjustment of the wear plates is more time consuming and additional holes must be provided in the flighting of the auger.
Therefore, a primary object of the present invention is the provision of an improved auger having adjustable wear plates on the outer peripheral edges of its flighting.
A further object of the present invention is the provision of a wear plate for the auger which can be rigidly held against movement by a pair of bolts, one located each end of the wear plate.
A further object of the present invention is the provision of an improved wear plate which can be held against inner radial movement without the need of blocking plates such as used in prior art devices.
A further object of the present invention is the provision of a wear plate which can be adjusted radially inwardly and outwardly more quickly than prior devices.
A further object of the present invention is the provision of a device which is simpler in construction and which resists to a better degree the forces which are encountered by the outer peripheral edges of the wear plates.
A further object of the present invention is the provision of a device which is economical to manufacture, durable in use and efficient in operation.